Cylinder construction for trunk piston engine

ABSTRACT

Cylinder construction for easily taking out the piston from the engine characterized by that the each cylinder liner can be removed in the crankcase and each piston can be rotated in the crankcase together with the connecting rod to a suitable position where the piston is taken from the engine.

[451 Jan.115,11974 123/DIG. 6

CYLINDER CONSTRUCTION FOR TRUNK 1,597,706 8/1926 Aldous.,.......................... PISTON ENGINE Inventor: Takeo Okazaki, Tokyo, Japan FOREIGN PATENTS F APPLICATIONS 6,152 5/1911 Great Br|ta1n.........,.......

Assignee: Mitsui Shipbuilding and Engineering 960,578 10/1949 France Co. Ltd., Tokyo, Japan 503,261 4/1939 Great Britain..............

Filed: Apr. 12, 1972 Primary Examiner-Wendell E. Burns Appl' 243l27 AttorneyHowson and Howson and Henry H.

Foreign Appllication Priority Data Skinman May 31, 1971 mmw tla E e c d e n h a t uew Oh gtk nm hm a y W W A m m wh r d S mme B f V A ao m mm r u e e mm n n ona ec re e kmn H I N hm 5 me r1 Cfd w n 7 MINE O0 9mMD2 3 7 mu k 1 ,m5 WHWW 5 R Q 5 m 9 "m l .u 3 "U 2 u m Mn N .r u a u u m a .M S ole I I U Mn. N Hod 5 55 1 11 piston can be rotated in the crankcase together with the connecting rod to a suitable position where the [56] References Cited UNITED STATES PATENTS piston is taken from the engine.

2,332,092 10/1943 Lieberherr..................... 123/D1G. 6 3 Claims, 6 Drawing Figures PAIENTED 1 3,785,357

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PAIENTEDJANI5I974 1785,35?

saw u or 4 FIGA CYLINDER CONSTRUCTION lFOlR TRUNK PIS'IUN ENGINE This invention relates to cylinder construction of the trunk piston engine for taking out the piston.

For the inspection and maintenance of the piston and piston ring of internal combustion engine the piston is usually taken from the engine. Usually, the piston is taken from the engine by removing a cylinder head cover and then upwardly drawing the piston. In order to perform the removing work of the cylinder head cover, such associated works as separation of the cylinder head piping, separation of valve actuating mechanisms and releasing of cylinder head cover fastening bolts are necessary, which requires much labor.

Therefore, an object of the present invention is to provide an engine construction which eliminates the above drawbacks and permits to take the piston from the engine with minimum of works.

To this end, the present invention is characterized by that the piston is taken from the cylinder together with the cylinder liner or with a part of the cylinder liner without removing the cylinder head cover.

FIG. I is a sectional view showing an embodiment of the present invention;

FIGS. 2 to 4 are show other embodiments of the present invention respectively;

FIG. 5 is a section view taken on line A-A in FIG. 3; and

FIG. 6 is a sectional view taken on line BB in FIG. 4.

Referring now to the drawings and particularly to FIG. 1, cylinder liner is divided into an upper halffi and a lower half 7 near at the top of the piston II positioned in the bottom dead point. The lower liner half 7 is fastened by bolts 12 to a cylinder block I and supported by a band 9 provided in the frame Ill. The top of the piston II is in the lower position than the frame 10 at its bottom dead point.

To take the piston from the engine, the crankshaft is turned to bring the piston to the bottom dead point as shown by solid lines, and then the lower liner half fastening bolts I2 are removed. Also, the head 9 is released, and the lower liner half 7 is lowered passing through the band 9 as the guide in the axial direction and put on the balance weight I3 mounted on the crankshaft as shown by broken lines. The lower liner half 7 and the balance weight I3 are tied together by a suitable means, and then the band 9 is removed. In this state, the lower liner half '7, piston II and connecting rod are integral with each other. By turning the crankshaft to the position of broken lines the piston may be taken out of the crankcase.

FIG. 2 shows the same construction as above em bodiment which is applied to a straight type engine. In the figure, the same parts as those in FIG. I are designated by same reference numerals as those used in the above case. In this example, the piston can be taken out in the same way as in the previous example. FIG. 3 shows still another embodiment. In this embodiment the cylinder head I and the liner 7a are engaged with each other at I6, so that the liner 7a is drawn downwardly for an increased distance. To this end, the balance weight I3 is formed with a groove H7, in which the liner is engaged when lowered.

FIG. I shows the construction applied to a straight type engine. In this example, the piston is taken out in the same way as the example of FIG. 3.

It will be apparent from the foregoing that the piston which is assembled in the engine in a relatively inner position therein can be taken out with a minimum of work without removing the cylinder head cover, so that the time and labor required for the inspection and maintenance may be greatly decreased.

What is claimed is:

I. In a trunk piston engine having a crankshaft rotatable about an axis of revolution, a crank on said shaft offset to one side of said axis of revolution, and a balance weight offset to the opposite side of said axis of revolution, a cylinder in said engine having its axis disposed radial to said axis of revolution, a piston mounted for axial displacement in said cylinder, and a connecting rod having means at one end rotatably mounting said rod on said crank and means at the other ends rotatably mounting said rod on said piston, whereby rotation of said crankshaft on its axis of revoltuion reciprocates said piston in said cylinder, said cylinder having a cylinder liner comprised of two axially aligned, endWise-abutting cylindrical parts within which said piston is displaced, said engine including a frame fixedly mounting the outermost cylinder liner part and means releasably mounting said inner cylinder liner part to said frame, the method of removing the piston and cylinder liner comprising the steps of rotating the crankshaft to position the piston at the bottom dead-center position in said cylinder liner, releasing the inner part of said cylinder liner from said frame and displacing said part axially inward into engagement with said balance weight, tying the liner part and the balance weight together, turning the crankshaft together with the connecting rod, piston and cylinder liner part to a position for convenient removal of said piston and cylinder liner from the engine, and thereafter removing the piston and cylinder liner part from the connecting rod and the balance weight.

2. A method according to claim I wherein said engine includes a band mounted on said frame and surrounding said inner cylinder liner part to support said part in position when it is mounted to said frame, said method including the step of releasing the band prior to displacement of said cylinder liner, utilizing said band as a guide for displacing said cylinder liner into engagement with said balance weight, and thereafter removing said band prior to turning said crankshaft.

3. A method according to claim 1 including the additional steps of providing a recess in said balance weight to provide a seat for said cylinder liner part and of engaging said part in said recess prior to completing the steps of tying said part and said weight together. 

1. In a trunk piston engine having a crankshaft rotatable about an axis of revolution, a crank on said shaft offset to one side of said axis of revolution, and a balance weight offset to the opposite side of said axis of revolution, a cylinder in said engine having its axis disposed radial to said axis of revolution, a piston mounted for axial displacement in said cylinder, and a connecting rod having means at one end rotatably mounting said rod on said crank and means at the other ends rotatably mounting said rod on said piston, whereby rotation of said crankshaft on its axis of revolution reciprocates said piston in said cylinder, said cylinder having a cylinder liner comprised of two axially aligned, endwise-abutting cylindrical parts within which said piston is displaced, said engine including a frame fixedly mounting the outermost cylinder liner part and means releasably mounting said inner cylinder liner part to said frame, the method of removing the piston and cylinder liner comprising the steps of rotating the crankshaft to position the piston at the bottom dead-center position in said cylinder liner, releasing the inner part of said cylinder liner from said frame and displacing said part axially inward into engagement with said balance weight, tying the liner part and the balance weight together, turning the crankshaft together with the connecting rod, piston and cylinder liner part to a position for convenient removal of said piston and cylinder liner from the engine, and thereafter removing the piston and cylinder liner part from the connecting rod and the balance weight.
 2. A method according to claim 1 wherein said engine includes a band mounted on said frame and surrounding said inner cylinder liner part to support said part in position when it is mounted to said frame, said method including the step of releasing the band prior to displacement of said cylinder liner, utilizing said band as a guide for displacing said cylinder liner into engagement with said balance weight, and thereafter removing said band prior to turning said crankshaft.
 3. A method according to claim 1 including the additional steps of providing a recess in said balance weight to provide a seat for said cylinder liner part and of engaging said part in said recess prior to completing the step of tying said part and said weight together. 